Process of molding plastics.



Sydney,

UNITED STATES PATENT OFFICE.

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l llrawing'. Original application filed March 18, 1813, Serial No. 754,008. Divided and this iiled March 18, 1915. Serial No. 15,315.

To all whom it may concern:

Be it known that we, EDWARD GILES STONE and ERNEST JOSHUA SIDDELEY, citizens of the Commonwealth of Australia, residin at in the State of New South ales and Commonwealth of Australia, have 1nvented certain new and useful Improvements in Processes of Molding Plastics, of which the following is a spec1fication4 This is a division of our application Serial No. 754,006, filed March 13th, 1913.

The invention to b described relates to a process or method of molding articles from lasties such as cement, concrete and the lite, the main object being to produce a hard, compact m'olded article from which the moisture is expelled in the molding operation and which shall have an even surface and beef equal consistency throughout.

To accomplish these'objects we introduce air under pressure into a suitable receptacle or reservoir containin a su ply of the plastic material; to be inol ed. rom this reseryoir we feed the material intoa suitable mold,

the latter being moldto allow equal escape ofair and moisture from the plastic .material. Simulta-. neously we tap the core of the mold at mi merous points by supply air under pressureto the mold'simulthe material thereto,

. taneouslywith' feeding thus further aiding 1n expelling the moisture. There will be no air pressure. inthe mold itself unless thesup 1y of air should exceed the aggregate out ow through-the various opemngs; but the re'ssur on the airsup' l ed to the mold wi l'ins'ure a good '45- flow 0 air through thalatter and conse-,'

quent thOIQiI Eh evaporation and removal of moisture; is process insures solid packal, therefore an even sur- Specification of Letters Patent.

provided witha pluralityof small outlets distributed evenly over the Patented Jan. 16, 1917.

application nor desirable to illustrate any particular mechanism or mode of operation.

Having thus described our invention, what we claim as new and desire to obtain by Letters Patent isz- 1. A process for molding plastics comprising, supplying air unde pressurev to an air tight reservoir containin molded and, next, feedin this material to a suitable mold while un or such ressure', allowing the simultaneous escape 0' air and the materialto be moisture freely through perforations'in all parts of said mold.

2 A process for moldingplastics, consisting of the following steps, first, supplyin air under 1s pressure to an air tight receptac e or're'servoir containing the material to be molded, second, feeding this" material to a suitable mold while simultaneously supply ing air under pressure directly to said mo d throu h holes to all parts of said-mold.

3. rocess for molding plastics consist eeding plastic material to a mold from 'which escape at all points and jarring said mold to reventadhesion of such material.

, n testimony whereof, we have signed our names tosthis specification in thepresence oftwo subscribing witn V .EDWARD GILES STONE. ERNEST JOSHUA SIDDELEY.

Witnesses:'- JOHN'JABPER S'ronn,

' Ma'n'r air and moisture are free to" and'allowing the escape. of air andmoisture 

